Permanent Reservoir Monitoring

Permanent monitoring solutions detect subtle reservoir changes, enabling asset teams to better understand the dynamic behavior of their reservoir. This increased understanding can lead to improved oil and gas recovery.

Installing seismic sensors permanently on the seafloor maximizes seismic signal recovery from reservoir zones, allowing much smaller production-related changes to be detected over shorter repeat intervals than can be achieved with time-lapse towed streamer surveys.

PGS OptoSeis® uses sensors that have been optimized for permanent installation, with recording technology that provides superior dynamic range and the broadest seismic bandwidth.

Utilizing optical fiber technology, PGS OptoSeis has no in-sea electrical components, making the system more reliable, safer and easier to deploy.


PRMPGS OptoSeis employs fiberoptic transmission, with a lower noise floor, reduced crosstalk and superior scalability compared to other systems.

From design to installation, acquisition, imaging, and interpretation, PGS provides a full turnkey solution for permanent reservoir monitoring, so our clients can enjoy excellent data quality for the life of the field.

For more technical details see the PGS Optoseis spec sheet

Design and 4D Feasibility

Front-end engineering design (FEED), 4D feasibility modeling, and advanced survey planning are the first steps in every PGS Optoseis project. We endeavor to understand the reservoir and its development over the production cycle before the first receiver is built, in order to optimize cost-benefit and PRM performance.

Survey design and feasibility studies are conducted using Nucleus® modeling software. The Nucleus toolbox includes state-of-the-art modeling approaches ranging from ray-tracing and illumination modeling to iterative visco-elastic full waveform modeling in up to three dimensions.

Full wavefield finite difference modeling using Nucleus simulates the detectability of weak 4D responses

We employ a wide range of input information, including geological and petrophysical information from existing reservoir data, seabed conditions, and existing or planned infrastructure. 4D rock physics models are combined with the latest acquisition and processing technologies to determine what timescale changes in the reservoir will be observable.

Results are analyzed by our team of expert geophysicists and subsea engineers to determine the best acquisition parameters and equipment layouts, embracing existing and next-phase production equipment.


A successful PRM project depends on more than monitoring. PGS OptoSeis comes with the PGS advantage of world-class HSEQ, financial stability, global presence, and marine operations experience. PGS has helped define international standards and best practices for marine installation of PRM systems.

Installation of OptoSeis

Our full-service installation solutions are designed to guarantee not only system performance but also maximum data value long after the first shot. The significantly lower operational cost of repeat surveys offered by a PGS OptoSeis installation quickly makes better economic sense than 4D alternatives such as OBC, nodes, and towed streamers. Various funding models are possible to suit your project.

From installation to decommissioning, over the entire operational life of the installation, the global PGS OptoSeis field services team offers 24/7 offshore support.

Time-Lapse Acquisition

PGS source steering techniques allow dynamic lateral source correction of more than ± 30m, assuring the highest level of repeatability. High-density 4D acquisition was pioneered by PGS. It ensures redundancy of shot and receiver pairs during 4D binning and survey matching. Nucleus source modeling is used to optimize source output for full-azimuth coverage. Collectively, these technologies allow optimum control over source positioning, improving uptime and sail line repeatability.

Passive Monitoring

Continuous passive monitoring provides decision-relevant reservoir information in real time, before the next time-lapse snapshot becomes available. Highly sensitive broadband sensors and advanced multicomponent analysis techniques enable the detection of the tiny microseismic emissions and subtle velocity variations that are indicative of the response of the reservoir and overburden to production and injection.

Fluid-induced seismicity provides valuable information for hazard monitoring and assessment, as well as geomechanical, dynamic reservoir characterization. Real-time monitoring and analysis can provide direct feedback to reservoir management when it is most needed.